for /fɔr; unstressed fər/ Show Spelled[fawr; unstressed fer] Show IPA preposition 1. with the object or purpose of: to run for exercise. 2. intended to belong to, or be used in connection with: equipment for the army; a closet for dishes. 3. suiting the purposes or needs of: medicine for the aged. 4. in order to obtain, gain, or acquire: a suit for alimony; to work for wages. 5. (used to express a wish, as of something to be experienced or obtained): O, for a cold drink! from dictionary.com LOL! learn the definition of "for"
For – Greek word εἰς - into, unto, to, towards, for, among.
"For" (as used in Acts 2:38 "for the forgiveness...") could have two meanings. If you saw a poster saying "Jesse James wanted for robbery", "for" could mean Jesse is wanted so he can commit a robbery, or is wanted because he has committed a robbery. The later sense is the correct one. So too in this passage, the word "for"signifies an action in the past.
http://www.searchgodsword.org/lex/grk/view.cgi?number=1519
Maybe it would be good for you to learn the meaning of the original words used instead of relying on just the English.